Patent GB-192173-A (GB)
Title: Improvements in the production of cellulose derivatives
IPC: D06M11/69
Filed: 1921-10-29
Abstract: Cellulose fibres such as cotton, linen, hemp, jute, and wood-pulp, either in the loose state or in the form of yarns or fabrics, are treated with inorganic acid chlorides such as thionyl chloride, sulphuryl chloride, pyrosulphuryl chloride, chlorsulphuric acid, and phosphoryl chloride; due to the formation of cellulose derivatives containing inorganic acidic groupings, the films or fabrics acquire properties differing markedly from those of the untreated material, for instance, they show an increased affinity for basic dyestuffs, fabrics made therefrom or so treated show in their fullness, elasticity, softness and warmth a resemblance to woollen fabrics, the treated yarns may be used as "effect" threads in mixed fabrics in order to produce coloured effects after dyeing, and wood-pulp or cotton so treated may be used for the manufacture of special qualities of paper where strength is required. In practice, the fibres, yarns, &c. are first treated with caustic alkali, and then either in the wet state or after drying, are treated with the inorganic acid chloride preferably at a temperature not exceeding 40 DEG C. and employing the chloride in the liquid or vapour form, but preferably dissolved in paraffin, petrol, chlorinated hydrocarbons, etc.; it is preferred to apply the acid chloride to the dry material, the drying being effected if in the presence of air rapidly and at a temperature not exceeding 40 DEG C., or if in vacuo more slowly and at a temperature not exceeding 50 DEG C. To obtain an increased lustre, the yarn so treated may be subsequently mercerized, or the same effect may be obtained by applying tension in the case of yarn or pressure in the case of loose material, during the treatment with the acid chlorides.  An increase of elasticity is obtained by subsequently treating the yarn or fabric with caustic alkali solution of a strength above 6 per cent without the application of tension or pressure; or alternatively, by employing in the first stage of the process a caustic alkali solution above mercerizing strength and then treating with the acid chlorides without the application of tension.ALSO:Cellulose fibres such as cotton, linen, hemp, jute, and wood-pulp, either in the loose state or in the form of yarns or fabrics, acquire an increased affinity for basic dyes after treatment with inorganic acid chlorides such as thionyl chloride, sulphuryl chloride, pyrosulphuryl chloride, chlorsulphonic acid, and phosphoryl chloride.  The treated yarns may be used as "effect" threads in mixed fabrics in order to produce coloured effects after dyeing.  In practice, the fibres, yarns, &c. are first treated with caustic alkali, and then either in the wet state or after drying, are treated with the inorganic acid chlorides preferably at a temperature not exceeding 40 DEG  C. and employing the chloride in the liquid or vapour form, but preferably dissolved in paraffin, petrol, chlorinated hydrocarbons, etc.; it is preferred to apply the acid chloride to the dry material, the drying being effected if in the presence of air rapidly and at a temperature not exceeding 40 DEG C., or if in vacuo, more slowly and at a temperature not exceeding 50 DEG C.